The Cardiovascular System - The Heart And Blood Vessles (w8) Flashcards
What are the three types of circulation ?
- pulmonary
- coronary
- systemic
What is the difference between a pulmonary vein and a vein in the systemic system ?
Pulmonary vein = carry oxygenated blood towards the heart
Systemic vein = carry deoxygenated blood towards the heart
What is the difference between a pulmonary artery and an artery in the coronary or systemic circulation system ?
Pulmonary artery = carries deoxygenated blood away from the heart
Systemic/ coronary artery = carries oxygenated blood away from heart
What are some features of an artery ?
- carry blood away from heart
- don’t have valves
- carry blood at high pressure (90mmHg)
- have a smaller lumen
- have smooth muscle, allows contraction (Tunica media)
- thick layer of elastic tissue, handles high pressure (Tunica externa/ Adventia)
- has a flat layer of smooth squamous endothelium, allows smooth flow of blood (tunica interna)
What are some features of a vein ?
- carry blood towards the heart
- has about 75-80% oxygen saturation (blood is dark red)
- has a big lumen
- has valves present, for directed blood flow
- handles blood at a low pressure (8-10mmHg)
- doesn’t have any elastic tissue
- has smooth muscle with elastic fibres
What are the three types of capillary ?
- continuous
- fenestrated
- sinusoids
What is the structure of a continuous capillary ?
- found in smooth and skeletal muscle
- BBB - has a very tight junction, this restricts toxin exchanges
What are the features of a fenestrated capillary ?
- found in the intestinal villi, kidney glomeruli and endocrine cells.
- has higher permeability for larger biomolecules
What are the features of a sinusoids capillary ?
- found at the red bone marrow and liver
- has huge molecule perfusion
- blood cells, proteins and wastes
Give some features of the heart (size, weight, volume of blood pumped in a day and heartbeat) …
- size = 14cm long and 9cm wide (fist of your hand)
- weight = 300-500 grams
- heartbeat = 70-100/min = 115000/day = 3.5 billion in a lifetime
- volume of blood pumped in a day = 9000 L
What is the function of the Myocardium in the heart ?
Is cardiac muscle which contracts and relaxes
What is the function of the pericardium in the heart ?
Is a fibrous layer which provides elasticity and protection
What is the function of the pericardial cavity in the heart ?
Fills with fluid and is a shock absorber
Where do the left and right chambers of the heart pump blood to ?
Left = body pump (rest of the body)
Right = pulmonary pump (lungs)
What word describes the blood flow in an artery ?
Pulsatile
How do pulsatile arteries adjacent to vein complement the muscle ?
Complements the muscle pump/pressure and venous return
What happens to venous during inspiration ?
- diaphragm compresses abdomen cavity, increasing the pressure, pushing blood from the abdomen cavity to the thorax.
- this reduced pressure in the thorax the sucks the blood from the abdominal cavity into the thorax.
What happens to venous return during expiration ?
- the increased pressure in the thorax pushes the blood back into the heart.
- this then reduces the pressure in the abdomen causing the blood to be sucked from the lower part of the body.
What is varicose vein ?
Swollen and enlarged veins, that are usually blue or dark purple and occur typically on the leg.
- usually caused by weak vein walls and valves.
What is a pulmonary embolism ?
A pulmonary embolism is a blocked blood vessel in your lungs, if not treated quickly it van be life-threatening.
- main cause = blood clots that travel to the lungs from deep veins in the legs or rarely from other veins in the body (deep vein thrombosis). These clots cause block blood flow to the lungs.
What causes coronary thrombosis - myocardial infarction (MI) ?
-caused by a buildup of cholesterol and fats in the artery walls.
- causes infarct or death of some of the heart muscles and is associated with prolonged or excruciating central chest pain.
What’s is capillary perfusion ?
When a liquid usually water id pushed into the interstitial fluid in the capillary. This is usually used for the transport of high does do drug through a blood vessel, in this case the capillary. An example of a possible drug is an anti-cancer drug.
How are the dynamics of blood perfusion in the capillaries auto regulates ?
By chemical and myogenic mediators
What are the three major types of capillary structures/ fucntional features ?
- continuous capillaries
- fenestrated capillaries
- sinusoid capillaries
